Yellow fever is an acute viral disease transmitted by infected mosquitoes. It causes fever, jaundice and can potentially progress to bleeding, organ failure and death. The virus is transmitted between monkeys, mosquitoes and humans. Prevention focuses on vaccination and mosquito control measures.

1. yellow fever
Presented by,
Mrs,m.josephin,
tutor

2. introduction
 Yellow fever is an acute viral haemorrhagic disease
transmitted by infected female mosquitoes.
 The “yellow” in the name denotes the jaundice that affects
some patients.
 Caused by ARBOVIRUS.
Principally affects monkeys.
Transmitted by Aedes Mosquitos.

3.  Haemorrhagic fever with severe HEPATIC and RENAL
involvement.
 Jaundice with haemorrhagic manifestations like black
vomit (xekik), epistaxis and melena may be present.
 May progress to albuminuria, anuria, shock, agitation,
stupor and coma.
Death between 5th and 10th day of illness.
Fatality rate : 80%
Survivors have long lasting immunity.

4. Agent factors
 Agent: GROUP B - TOGAVIRUS- FLAVIVIRUS FIBRICUS.
 Reservoirs:
Forest cycle→ monkeys and forest mosquitoes.
Urban cycle→ man and Aedes Aegyptus mosquitoes.
 Period of communicability:
Man: 3-4 days of illness.
Mosquitoes: after “ the extrinsic incubation period”- 8
to 12 days.
Trans ovarian transmission- extended dry season in
absence of susceptible hosts.

5. host factors
 All age and both sex.
 Wood cutters and hunters are more prone.
 First attack→ long lasting immunity.

6. Environmental factor
ENVIRONMENTAL FACTORS:
CLIMATE: >24 deg C needed for the multiplication of
virus in mosquito.
 Relative humidity: >60%.
 Urbanization,travel & expanding population - closer to
jungles

7. Mode of transmission
There are three known cycles of transmission, the jungle, intermediate
and the urban cycles .
1. Sylvatic (or jungle) yellow fever :
 In tropical rainforests, yellow fever occurs in monkeys that are
infected by wild mosquitoes.
 The infected monkeys then pass the virus to other mosquitoes that
feed on them.
 The infected mosquitoes bite humans entering the forest, resulting in
occasional cases of yellow fever.
 The majority of infections occur in young men working in the forest
(e.g. for logging)

8. CONT.. 2. Intermediate yellow fever.
 In humid or semi-humid parts of Africa, small-scale
epidemics occur, Semi-domestic mosquitoes (that breed in
the wild and around households) infect both monkeys and
humans.
 Increased contact between people and infected
mosquitoes leads to transmission. This is the most
common type of outbreak in Africa

9. CONT.. 3. Urban yellow fever:
 Large epidemics occur when infected people introduce
the virus into densely populated areas with a high number
of non-immune people and Aedes mosquitoes.
 Infected mosquitoes transmit the virus from person to
person

10. clinical manifestations
ACUTE PHASE:
 Fever
 Shivering
 Muscle pain
 Back ache
 Head ache
 Loss of appetite
 Nausea and Vomiting

11. TOXIC PHASE:
 High body temperature
 Appearance of jaundice
 Has abdominal pain and vomiting
 Bleeds through the orifices like mouth, nose, eyes or
stomach. Blood found in vomit and feces.
 Kidney function Worsens.
 Shock, Agitation, coma and stupor
 Toxic phase may induce death.

12. Prevention andcontrol
vaccination:
 A single dose of live, attenuated vaccine 0.5 ml is given
subcutaneously at the site of insertion of deltoid muscle.
 The vaccine must be reconstituted immediately with the
sterile diluent provided (sodium chloride injection).
 The vaccine needs to be administered within 1 hour of
reconstitution.

13.  A multi dose vial should be maintained at 350F-460F
(20C-80C) .
 The remaining doses should be used or discarded within 1
hour.
 International Health Regulations(IHRs) require
revaccination at intervals of 10 years to boost antibody
titer.

14. Mosquito control measures
 Anti larval measures
Anti adult measures
Health education
Elimination of breeding places.

15. Protective measures for travellers
 Traveller must have valid vaccination certificate before
entering into yellow fever receptive area.
 If no proof traveller must be placed on quarantine for
6 days in a mosquito proof ward.
 In addition traveller are recommended to use insect
repellent, wearing permethrin impregnated clothing,
staying in screened or air-conditioned room.

16. treatment
There is no specific treatment for yellow fever, only
supportive care to treat dehydration and fever.
 Associated bacterial infections can be treated with
antibiotics. Supportive care may improve outcomes for
seriously ill patients.
INCUBATION PERIOD:
 3 to 6 days (6 days recognized under International Health
Regulations).

17. Japanese encephalitis

18. introduction
• Japanese encephalitis is a mosquito-borne viral
infection.
• Japanese Encephalitis is the inflammation of brain,
due to Group B Arbo virus transmitted by Culex
mosquitoes.
• It is directly affect to the central nervous system
and may cause severe complications.

19. incidence
 Japanese Encephalitis most common in Japan, widespread
throughout Southeast Asia.
 China, Korea, Japan, Taiwan, and Thailand have had outbreaks in
the past, but they have mainly controlled the disease by vaccination.
 In India, It was diagnosed first time in 1995 at Vellore, and in
Assam, UP,Bihar,TNhas been reported later.
 The majority of cases about 85% among children below 15 years of
age

20. Epidemiological triad
Agent
Host
Environment

21. agent
Group B Arbo virus in the genius group
of Flaviviridae
Domestic pigs and wild birds (especially
herons) are reservoirs of the virus.

22. host
 All age group and Both gender More in children under 15
years of age Environment Rainy season.
environment
 Rainy season

23. INCUBATION PERIOD
5-15 Days
CLINICAL MANIFESTATION
Clinical Manifestations Clinical features are divided into
3 stages
 Prodromal stage
 Acute Encephalitic stage
 Late stage

24. PRODROMAL STAGE
The onset of illness is usually acute & the duration of this stage
is usually 1-6 days.
Fever(38-41’c)
Headache
Rigors (Intensive shivering)
GI disturbances
Nausea & Vomiting
Lethargy

25. Acute Encephalitic stage
This stage begins by 3-5th day
 High grade fever
 Nuchal rigidity
 Convulsions signs of increased ICP
 Unconsciousness
 Dystonia
 Dysphasia
 Hemiplegia
 Quadriplegia

26. Late stage
This stage begins when active inflammation reduced
ie,the temperature & ESR touch normal.
• CNS involvement is more in this stage.
• Mental impairment
• Epilepsy
• Behavioural abnormalities.
• The average period between the onset of illness and death
is about 9 days only.

27. Laboratory diagnosis
Detection of Antigen from serum or cerebrospinal fluid
(CSF) to detect virus- specific IgM antibodies within 7 days
of onset of disease.
• Compliment Fixation Test: To detect the antibodies for
infection.
• Neutralization Test: To detect the presence of virus
infections.
• Immunofluorescence Assay: To detect the antigen &
antibodies

28. Prevention andcontrol
1. Early Detection, First Aid & Referral
2. JE can be recognised by following symptoms and first
Aid can be given by parents till the child is shifted to the
hospital;
3. Fever
4. Loss of consciousness or altered behavioural changes
over 1 hour to 4 days
5. Observe for new development of symptoms like
abnormal movements & posture,Squint,mouth deviating
to one side.

29. Shifting the patient to hospital
Keep the nose & mouth clean and saliva should be cleared
from mouth.
Keep the patient on one side with head in a little lower
position
If cold, wrap in a cloth & if fever, do sponging.

30. vaccination
Japanese encephalitis vaccine

31. Vector control
Chemical Control
• Insecticides.eg: malathion, fenitrothion
 Biological Control
• Larvivorous fish are those that feed on immature stages of
mosquitoes where the stagnation of water for their growth.
• Personal Prophylactic Measures
 Bed mosquito nets, wear long sleeves to cover the
exposure body parts,mosquito repellents.

32. management
Control Hyperthermia by hydrotherapy & antipyretics.
eg:Paracetamol
Manage convulsion with anti-convulsive drugs
Maintain ICP with initial dose of Mannitol solution to be
given.
After 30 minutes of mannitol infusion,re-assess the ICP
and still increased,then administer .
Symptomatic treatment

33. KYAsanur forest disease
PRESENTED BY
Mrs,M.Josephin
Tutor

34. KYAsanur forest disease
KFD is a tick-borne viral haemorrhagic fever endemic
(constant presence of disease) in Karnataka State, India.
It is also referred as monkey fever by local people.
The virus causing the disease: KFD virus
(KFDV) is a member of the genus Flavivirus and family
Flaviviridae.
 KFDV was first identified in 1957, when an illness occurred in
monkeys (the black faced langur and the red faced bonnet
monkey) in Kyasanur Forest area of Shimoga
district,Karnataka State along with febrile illness and few
deaths in humans in neighborhood

35. Epidemiological triad
agent
Flaviviridae
Rodents,
Shrews&
Monkeys
host
People between
20-40 years
Males
Cultivators
environment
spring
season
(Tropical
evergreen)

36. Mode of transmission
 By the bite of infective ticks
Human is dead end in the natural cycle
 There is no evidence of man to man transmission
incubation period
3-8 days

37. Clinical symptoms
 onset is sudden with fever, chills and headache.
 severe myalgia
Vomiting, gastro intestinal symptoms and bleeding
problem may occur
Hypotension with reduced platelet, RBC and WBC
Severe headache, mental disturbances, tremors and vision
deficit

38. diagnosis
 Diagnosis by a suspicion by clinical signs and symptoms
 H/O occupation/Travel in forests
 Detecting the presence of virus in the blood
 Serological evidence by haem agglutination and
immunofluorescence
 ELIZA Enzyme linked immunosorbent serologic assay can
be performed

39. Prevention andcontrol
• In activated chick embryo vaccine
• Risk population like villagers living near forest
and forest workers

40. control of ticks
 By aircraft mounted equipment to dispense the lindane,
cabaryl fenthion at 2.24kg/ hectare at forest floor
 Spraying carried out within 50m around hot spots
Restriction of cattle movement brings reduction in vector
populations

41. Personal protection
 Adequate clothing
 Insect repellents such as DMP,DEET Provide 100%
protection against tick bites.
Examine themselves for ticks and promptly remove them
Health education

42. chikungunya
PRESENTED BY
Mrs,M.Josephin
Tutor

43. introduction
• Chikungunya is a virus that is transmitted from human to human mainly by
infected Aedes albopictus and Aedes aegypti mosquitoes (later referred to as
Aedes mosquitoes) acting as the disease-carrying vector
• Chikungunya causes sudden onset of high fever, severe joint pain, muscle pain
and headache
• As no vaccine or medication is currently available to prevent or cure the
infection, control of Chikungunya involves vector control measures and
encouraging people to avoid mosquito bites

44. Epidemiological triad

45. AGENT
 It is an RNA virus that belongs to the alphavirus genus of
the family Togavirus

46. Host factors
 The virus is transmitted from human to human by
bites of infected female mosquitoes.
 The mosquitoes involved in transmitting the
disease are Aedes aegypti and Aedes albopictus

47. Environment factor
 The closeness of mosquito vector breeding sites to human
dwelling is a significant risk factor
One should keep the living and working places clean.

48. symptoms
 Fever typically ranges from 1020 F- 1040 F
Disabling joint pain
Maculopapular rashes

49. Prevention and control
ENVIRONMENTAL CONTROL
 Reducing the number of natural and artificial water filled
containers that largely support mosquito breeding
 During epidemics, spraying of insecticides to kill
mosquitoes, surfaces of containers where the mosquitoes
stay and water containers in which immature larvae live.

50. Personal protection
 Clothing which minimizes skin exposure to the day-biting vectors
 When possible ,clothes can be treated with permethrin to repel
mosquitoes
 Application of repellents
Integrated Vector Management
 Source Reduction
 Larvicidal agents (Temephos)
 Adult mosquito control(Pyrethrum extract)
 Biological Control
 Legislative measures
 Capacity building